The invention is directed to an improved retention system, and in particular to an improved locking latch for retaining electrical terminals within connector housings, and a secondary locking mechanism therefor.
There are many applications for electrical connectors where the interconnection is subject to adverse conditions, such as high vibrations, inclement weather requiring sealing, and the like. Such is the case in automotive electrical systems. Furthermore, it is desirable to minimize the size of the electrical connectors and their corresponding contacts to provide for a high density of electrical connections. As the size of the electrical connector is reduced, the challenges associated with the connector design are increased. For example, the contacts must still be retained within the housings, yet the magnitude of the mechanical forces that can be exerted to retain the contacts within their corresponding housings is reduced. As a result, in high vibration environments, the magnitude of the mechanical force may not be sufficient to retain electrical contacts in their corresponding housings.
In order to assure the primary retention of a socket-type electrical contact as described above, it is known to include a locking latch or lance, which is integral with the housing. This locking latch normally depends from a housing side wall, and depends into the terminal passageway. The latches need to be resilient because the terminals are inserted into the passageways, where the latches are resiliently biased to allow insertion, and then snap back into a retentive position. When the connector housing are reduced in size, all of the components also must be reduced, and in the case of a reduction in length, the length of the locking latches must be proportionately reduced in length. The problem associated with reducing the length of the locking latch is that the latches are less resilient and in some cases brittle, and can either snap off or take on a plastically deformed set.
One interconnection commonly used in high vibration environments is between a pin- or tab-type terminal and a socket-type electrical contact which is retained in a connector housing that is adapted to mate with the component containing the tab-type terminal. A known socket-type electrical contact includes two opposing contact arms that are constricted to engage the tab-type terminal therebetween and exert a normal force against the tab. The contact arms are interconnected to a central body that commonly form into a box like member. A transition section extends from the central body opposite the contact arms to a conductor engaging portion that may be adapted to be crimpably attached to a conductor, such as an insulated wire.
It is also known to provide a secondary locking feature that mechanically locks the electrical contact to the housing within which it is disposed. The secondary locking member is typically a non-conductive component which may, or may not, be integrally formed as part of the connector housing and includes a bearing surface, or an engaging surface, that blocks the contact to prevent displacement thereof. The contact must contain a complementary bearing surface that is engageable or abuttable by the secondary locking member so that movement of the contact may be opposed. It is known to provide the secondary locking between the bearing surface of the secondary lock with an edge of the central body of the terminal to be locked.
Thus, the problems associated with the reduction in size of the connectors is that the housing become so small that no resiliency exists in the locking latch, and there is no provision, or no space for provision of, a secondary lock member for secondarily locking the terminals in place.
The objects of the invention are therefore to provide solutions to one or more of the shortcomings mentioned above.